SSRS Report keeps Timing out

Question

SSRS Report keeps Timing out

Corey Fleig 510

I wrote an SSRS Report that runs a stored proc, outputs data to a shared drive as a TEXT file.

The file is 50MB, but sometimes it doesn't time out, sometimes it does. I have adjusted the timeout settings in both VS and in the SSRS subscription dialog. But still I can't seem to nail down the problem. The message is this:

Error: Execution Timeout Expired. The timeout period elapsed prior to completion of the operation or the server is not responding.

The only mod is that I changed the global config file to create pipes for delimiter, not commas. That shouldn't affect this. IS it size, or connectivity? The message appears immediately, so I thought connectivity, but I have no idea what's its complaining about. I have about 200 other scheduled reports that are flawless, but this isn't happening!

any thoughts?

Corey Fleig 510 Reputation points

2026-09-09T23:37:30.4766667+00:00

Followup: I'm using a data subscription service. I adjusted the dataset timeout and the server side timeout to 3600.
Deepesh Dhake 1,165 Reputation points

2026-09-10T03:23:53.9+00:00

Does it still fail after setting 3600, and if so, how fast? If it fails in 30s despite 3600, some layer is ignoring your setting. Is the "data subscription service" native SSRS or a third-party tool? If third-party, its own timeout is my prime suspect.
Corey Fleig 510 Reputation points

2026-09-10T19:58:45.4933333+00:00

Its failing all the time, right from the start. I'm using Microsoft Reporting Services, and the report uses a Data Driven Subscription. I suspect this is the issue, because it works great with a standard subscription and never times out.

The problem is that I need to customize the output filename with {filename}_mmddyyyy.txt. I would stick to standard if I could. The Data driven subscription just executes a proc with no parameters, and outputs to a file. I have made really sure that all 3 timeout settings are right: dataset timeout, data source timeout, and server timeout. I'm baffled.
Corey Fleig 510 Reputation points

2026-09-10T19:59:52.3+00:00

BTW I'm a SQL database developer, so the advice from PiusR might be right, but I don't understand any of that. My fault!
Erland Sommarskog 137.4K Reputation points MVP Volunteer Moderator

2026-09-10T20:08:36.9733333+00:00

It you get the timeout error about immediately, that would suggest that you have a very narrow setting for the query timeout like 1, that is 1 second. The default is 30 seconds in most environments.

I don't know anything about SSRS, so I can't say where you control this setting. But it is not the data-driven subscription per se that is the problem, but that that subscription for some reason has a funny value.
Corey Fleig 510 Reputation points

2026-09-10T22:22:13.5666667+00:00

I set all 3 timeouts (dataset, data source, and report service) to 1 hour. Still aborts.
Deepesh Dhake 1,165 Reputation points

2026-09-11T00:53:34.2333333+00:00

The data-driven path adds a settings query that the standard path doesn't, and you've confirmed standard works - so the fault is very likely in what data-driven adds. What's speculative: that SSRS is disguising a settings-query failure as a timeout message.

You can check the real error in the ReportServer log:

...\Reporting Services\LogFiles\ or the ExecutionLog3 view in the ReportServer DB.

3 answers

Your answer

Corey Fleig 510 Reputation points

2026-09-09T23:37:30.4766667+00:00

Followup: I'm using a data subscription service. I adjusted the dataset timeout and the server side timeout to 3600.
Deepesh Dhake 1,165 Reputation points

2026-09-10T03:23:53.9+00:00

Does it still fail after setting 3600, and if so, how fast? If it fails in 30s despite 3600, some layer is ignoring your setting. Is the "data subscription service" native SSRS or a third-party tool? If third-party, its own timeout is my prime suspect.
Corey Fleig 510 Reputation points

2026-09-10T19:58:45.4933333+00:00

Its failing all the time, right from the start. I'm using Microsoft Reporting Services, and the report uses a Data Driven Subscription. I suspect this is the issue, because it works great with a standard subscription and never times out.

The problem is that I need to customize the output filename with {filename}_mmddyyyy.txt. I would stick to standard if I could. The Data driven subscription just executes a proc with no parameters, and outputs to a file. I have made really sure that all 3 timeout settings are right: dataset timeout, data source timeout, and server timeout. I'm baffled.
Corey Fleig 510 Reputation points

2026-09-10T19:59:52.3+00:00

BTW I'm a SQL database developer, so the advice from PiusR might be right, but I don't understand any of that. My fault!
Erland Sommarskog 137.4K Reputation points MVP Volunteer Moderator

2026-09-10T20:08:36.9733333+00:00

It you get the timeout error about immediately, that would suggest that you have a very narrow setting for the query timeout like 1, that is 1 second. The default is 30 seconds in most environments.

I don't know anything about SSRS, so I can't say where you control this setting. But it is not the data-driven subscription per se that is the problem, but that that subscription for some reason has a funny value.
Corey Fleig 510 Reputation points

2026-09-10T22:22:13.5666667+00:00

I set all 3 timeouts (dataset, data source, and report service) to 1 hour. Still aborts.
Deepesh Dhake 1,165 Reputation points

2026-09-11T00:53:34.2333333+00:00

The data-driven path adds a settings query that the standard path doesn't, and you've confirmed standard works - so the fault is very likely in what data-driven adds. What's speculative: that SSRS is disguising a settings-query failure as a timeout message.

You can check the real error in the ReportServer log:

...\Reporting Services\LogFiles\ or the ExecutionLog3 view in the ReportServer DB.

Answer 1

Most SSRS time-out errors occur during query processing. The first check is to make sure the query time-out and the report execution time-out are aligned correctly.

Increase the dataset query time-out where the report is authored.
- In Report Builder: Report Data pane → right-click the dataset → Dataset Properties → Query tab → set Time out.
- For paginated reports in Power BI, the default is 600 seconds.
If the report uses a shared dataset, set its server-side query time-out.
- In the web portal: Browse → More Info → Manage → Properties → Query time-out in seconds.
- The default for a shared dataset is 0 seconds, which means no time-out.
Increase the report execution time-out so it is larger than the query time-out.
- In the web portal for a specific report: Browse → More Info → Manage → Properties → Advanced → Report time-out.
- The default report execution time-out is 1800 seconds.
- If the query time-out is higher than the execution time-out, SSRS can still stop processing before the query finishes.
Be aware that report execution time-outs are evaluated every 60 seconds.
- SSRS checks running jobs at 60-second intervals.
- Because of that, behavior can appear inconsistent: a report can sometimes complete and sometimes be stopped depending on where it falls in that cycle.
For large reports, reduce on-demand execution where possible.
- Configure the report to run as a scheduled report snapshot.
- Run it during off-peak hours.
- For large outputs, rendering format matters: CSV, XML, and HTML are faster and use less memory than PDF or Excel.
If the report is delivered by subscription, increase the subscription query time-out on the Edit Subscription page.
- That setting controls how long the report server waits when retrieving data for the subscription.

Based on the symptoms described, the most likely issue is not the delimiter change itself, but a mismatch between query time-out and report execution time-out, combined with the variability of large report processing. Since the error is intermittent, start by setting the execution time-out higher than the query time-out and then move the report to scheduled snapshot processing if it is still unstable.

Answer 2

The error is the SQL query timing out (.NET CommandTimeout) - not connectivity, and not the VS or subscription timeouts you already adjusted. The setting to change is the dataset/data source query timeout. Try setting it to 0 and retest.

The most likely cause is blocking or parameter sniffing, both of which fit the "usually fine, sometimes not" pattern. You can catch blocking with sp_WhoIsActive during a run, and test the sniffing theory with OPTION (RECOMPILE).

Two things would help pin it down: does it fail after roughly 30 seconds or truly instantly, and how long does the proc take in SSMS with the same parameters?

Answer 3

Worth to also check: After you have changed the global rsreportserver.config for the delimiter, did the report server app pool make a recycle? Because such a config change is restarting the service, so the first run(s) after that are having additional cold-start cost on top of the normal query time — this could explain why it is sometimes timing out and sometimes not, independent from the 3600s settings you have already adjusted. You can check the ReportServerService trace log timestamp of the failing run against the timestamp of the config change / app pool start, to confirm this.